Mozilla announced, just yesterday, some big improvements in the extension review process, including adding more reviewers:
https://blog.mozilla.org/addons/2016/03/04/breakthroughs-in-...
https://blog.mozilla.org/addons/2016/03/04/breakthroughs-in-...
Another aside: At least for extensions featured in a store, it makes sense to me to have a vetting process. Also, I believe that anyone should be able to read, unminified, the code they run on their computers if they so wish. (Especially if the software gets to view/change the content of the pages they visit.) So, I appreciate the general rule in Moz's review process against minified code and large unknown libraries.